The present invention relates to a waterproof switch apparatus for an electronic device.
FIG. 4 shows a structure of a conventional waterproof switch for an electronic device. In FIG. 4, numeral 1 denotes a push-button, which is mounted on a device body 4 with its head portion 1a borne by a return spring 2 and with its shaft portion 1b fitted with a E-ring 3. Numeral 5 denotes a waterproof ring, which is fitted in an annular groove 1c formed on the peripheral . surface of the shaft portion 1b of the push-button 1 and in close contact with the device body 4, thereby preventing water from intruding into the inside of the device body 4. Numeral 6 denotes a printed circuit board, and numeral 7 a diaphragm mounted on the printed circuit board 6 at a position opposite to the tip portion of the shaft portion 1b of the push-button 1.
The function of the above-mentioned conventional push-button switch is described below. In FIG. 4 , when the push-button 1 is pushed down, the tip portion of the shaft portion 1a pushes the diaphragm 7, thereby closing a contact mounted on the printed circuit board 6 for sending electric power. When the pushing force against the push-button 1 is released, the push-button returns to its original position by the help of the elastic force of the return spring 2, thereby also returning the diaphragm to its original position and opening the contact.
Since a waterproof rubber ring 5 is provided between the shaft portion 1b of the push-button 1 and the device body 4, intrusion of water into the inside of the device body 4 is prevented.
Thus, in the above-mentioned conventional waterproof switch for an electronic device, water intrusion into the inside of the device body can be also prevented by use of a waterproof rubber ring.
The above-mentioned conventional waterproof switch includes, however, a problem that there is required a space for permitting the plate spring 2 to deform and in addition, a space for permitting the waterproof rubber ring 5 to move in close contact with the device body 4, and as a result, the switch as a whole and the device body 4 as well become thick.